Can OES data be used to compare changes in employment or wages over time?
Although the OES survey methodology is designed to create detailed cross-sectional employment and wage estimates for the U.S., States, metropolitan and nonmetropolitan areas, across industry and by industry, it is less useful for comparisons of two or more points in time. Challenges in using OES data as a time series include changes in the occupational, industrial, and geographical classification systems, changes in the way data are collected, changes in the survey reference period, and changes in mean wage estimation methodology, as well as permanent features of the methodology. Changes in occupational classification The OES survey used its own occupational classification system through 1998. The 1999 OES survey data provide estimates for most of the nonresidual occupations in the 2000 Standard Occupational Classification (SOC) system. The 2004 OES data provides estimates for all occupations in the 2000 SOC. Because of these changes, it may be difficult to compare some occupations eve
